Physiological effects induced by stimulation of cutaneous sensory nerves, with a focus on oxytocin

Gentle touch is mediated by CT afferents and is linked to the experience of pleasure by effects in the insular cortex. It is also associated with some antistress effects, lower levels of anxiety and pain reduction. A similar effect pattern is induced by oxytocin. In the present article, we describe the structure of the hypothalamic oxytocinergic system, in particular the pathways involved in reduction of anxiety, stress and pain. We detail how oxytocin exerts powerful anti-stress effects by antagonizing the release of and effects of corticotrophin releasing factor (CRF) and noradrenaline (NA), the main central regulators of the hypothalamo-pituitary-adrenal (HPA) axis and of the autonomic nervous system. It is suggested that CT fibers connect to the oxytocin system, and that oxytocin mediates the decrease of sympathetic nerve activity, increase of parasympathetic nerve activity as well as the reduction of pain and anxiety, induced by gentle touch. Thus, by reducing stress, repeated activation of CT afferents may be linked to better health.